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Copper Pipe Friction Loss Tables

How To Use a Pipe Pressure Loss Table:

(PSI = pounds per square inch = lbs/sq.in.)

Select the proper table for the type of pipe. Type K copper pipe has the thickest wall and highest pressure ratings of the common copper tubing types. In order of wall thickness, common copper tubing types are Type M (thinnest), Type L, and Type K (thickest). Type L is commonly used for household plumbing. If you don't know what Type the pipe is, assume it is Type K.

Locate the proper column on the table for the pipe size.

Read down the column to the row for the flow rate (GPM) in the pipe section. You will find a PSI loss value (given as PSI/100).

Multiply the PSI loss value shown by the total length of the pipe section, then divide the product by 100. (PSI loss on these tables is given in PSI per 100 feet of pipe.)

Value * Length / 100 = PSI loss

Pressure Loss Table, Type K Copper Pipe or Tubing

Flow in GPM

1/2"

3/4"

1"

1 1/4"

1 GPM

1.20

0.23

0.05

0.02

2 GPM

4.33

0.77

0.18

0.06

3 GPM

9.17

1.65

0.38

0.13

4 GPM

15.67

2.78

0.68

0.22

5 GPM

4.21

1.02

0.33

6 GPM

5.90

1.44

0.46

7 GPM

7.84

1.90

0.61

8 GPM

10.03

2.46

0.78

9 GPM

12.48

3.03

0.97

10 GPM

15.15

3.68

1.18

11 GPM

4.40

1.41

12 GPM

5.17

1.66

13 GPM

6.00

1.93

14 GPM

6.88

2.21

15 GPM

7.81

2.51

16 GPM

8.42

2.83

17 GPM

9.42

3.16

18 GPM

3.52

19 GPM

3.89

20 GPM

4.28

22 GPM

5.10

24 GPM

5.99

26 GPM

6.95

Velocities over 5 feet per second are shown in red and should be avoided.

Pressure Loss Table, Type L Copper Pipe or Tubing

Type L copper tube is the type most commonly used for household plumbing. In order of wall thickness, common copper tubing types are Type M (thinnest), Type L, and Type K (thickest). If you don't know what Type the pipe is, assume it is Type K.

Flow in GPM

1/2"

3/4"

1"

1 1/4"

1 GPM

0.95

0.16

0.04

0.02

2 GPM

3.44

0.57

0.15

0.06

3 GPM

7.29

1.20

0.33

0.12

4 GPM

12.41

2.05

0.56

0.20

5 GPM

18.77

3.09

0.85

0.30

6 GPM

4.34

1.18

0.43

7 GPM

5.77

1.58

0.57

8 GPM

7.39

2.02

0.72

9 GPM

9.19

2.51

0.90

10 GPM

11.17

3.05

1.10

11 GPM

3.64

1.31

12 GPM

4.28

1.54

13 GPM

4.96

1.78

14 GPM

5.69

2.04

15 GPM

6.46

2.32

16 GPM

7.28

2.62

17 GPM

8.15

2.93

18 GPM

9.06

3.25

19 GPM

3.60

20 GPM

3.96

22 GPM

4.72

24 GPM

5.55

26 GPM

6.43

Velocities over 5 feet per second are shown in red and should be avoided.